The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 13, 2001
Filed:
May. 27, 1998
Applicant:
Inventors:
Minsiu Huang, Saratoga, CA (US);
Jingwei Lin, Saratoga, CA (US);
Assignee:
ActionTec Electronics, Inc., Sunnyvale, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04M 1/100 ;
U.S. Cl.
CPC ...
H04M 1/100 ;
Abstract
Over-voltage protection circuitry for use with a PCMCIA modem card or a mobile modem is disclosed. The protection circuitry detects excessive voltage between the tip and ring lines of a telephone subscriber loop when the modem is “off-hook”, and immediately places the modem “on-hook”, protecting the line interface circuitry, when the over-voltage condition is detected. The over-voltage protection circuitry of the present invention may share common components and signal lines with the modem's ring-detection circuitry, and may be implemented using a minimal number of additional components.